Sensing single domains and individual defects in scaled ferroelectrics

Abstract

Ultra-scaled ferroelectrics are desirable for high-density nonvolatile memories and neuromorphic computing; however, for advanced applications, single domain dynamics and defect behavior need to be understood at scaled geometries. Here, we demonstrate the integration of a ferroelectric gate stack on a heterostructure tunnel field-effect transistor (TFET) with subthermionic operation. On the basis of the ultrashort effective channel created by the band-to-band tunneling process, the localized potential variations induced by single domains and individual defects are sensed without physical gate-length scaling required for conventional transistors. We electrically measure abrupt threshold voltage shifts and quantify the appearance of new individual defects activated by the ferroelectric switching. Our results show that ferroelectric films can be integrated on heterostructure devices and indicate that the intrinsic electrostatic control within ferroelectric TFETs provides the opportunity for ultrasensitive scale-free detection of single domains and defects in ultra-scaled ferroelectrics. Our approach opens a previously unidentified path for investigating the ultimate scaling limits of ferroelectronics.

Effects of Interface Oxidation on Noise Properties and Performance in III–V Vertical Nanowire Memristors

“…Figure 4d,f shows the trapping and de-trapping events for HRS currents versus time for samples with t plasma = 10 s and t plasma = 30 s. The characteristic capture time constant (τ c ) and emission time constant (τ e ) as shown in Figure 4e,g were determined by fitting an exponential distribution of the capture time (t c ) and emission time (t e ) indicated in Figure 4d. 26 The capture time constant and emission time constant for IL-oxide with t plasma = 10 s and t plasma = 30 s were determined to be τ c = 0.09 s, τ e = 0.03 s and τ c = 0.128 s, τ e = 0.19 s respectively. When t plasma = 10 s, we observe that τ c > τ e , and when t plasma = 30 s, we find τ e > τ c indicating the upward movement of the Fermi-level of IL-oxide with respect to the defect energy level.…”

“…Notably in Figure S5, no RTN was observed for t plasma = 80 s at V READ = 500 mV due to a likely reduction in trap density with increased oxidation. Figure d,f shows the trapping and de-trapping events for HRS currents versus time for samples with t plasma = 10 s and t plasma = 30 s. The characteristic capture time constant (τ c ) and emission time constant (τ e ) as shown in Figure e,g were determined by fitting an exponential distribution of the capture time ( t c ) and emission time ( t e ) indicated in Figure d . The capture time constant and emission time constant for IL-oxide with t plasma = 10 s and t plasma = 30 s were determined to be τ c = 0.09 s, τ e = 0.03 s and τ c = 0.128 s, τ e = 0.19 s respectively.…”

“…27 It can be observed from Figure 4d that the RTN is caused by more than a single trap indicating a higher trap density when t plasma = 10 s. The participation of at least two traps is indicated in Figure 4d, where the change in current (ΔI) after an electron is trapped for trap 1 and trap 2 is different, whereas when an individual defect is dominant for causing RTN, ΔI after charge trapping remains the same. 26 The presence of more than one trap makes it difficult to determine exactly a characteristic trap time constant but τ c > τ e changing to τ e > τ c with increasing IL-oxide thickness nevertheless indicates increased conductivity of the IL-oxide.…”

Anti‐Ambipolar Heterojunctions: Materials, Devices, and Circuits

“…The surface atoms of small molecular and polymeric organics possess saturated bonds, thus endowing them with vdW interactions for integration with other dangling bondfree vdW materials, e.g., 2D layered materials. [47,[142][143][144] From [97] a-e) Reproduced with permission. [97] Copyright 2023, Springer Nature.…”

“…[47,[142][143][144] From [97] a-e) Reproduced with permission. [97] Copyright 2023, Springer Nature.…”